The present invention relates to a method and devices that are useful for the performance testing of electrochemical cells.
Many potential uses for packaged power exceed the capacity of existing electrochemical cells, and much effort has been recently directed to the development of high energy density electrochemical cells. The ideal electrochemical cell would be one that could take full advantage of the differences in the electrochemical potentials between the highly electropositive alkali metals, particularly lithium, and the highly electronegative halides, particularly fluorine. The reactive nature of both the alkali metals and the halides make the use of these substances in electrochemical cells very difficult. The problems have caused much attention to be focused on the selection and preparation of cathode active materials and alkali ion conducting electrolytes that can be used in conjunction with alkali metal anodes.
The search for new battery systems is normally a time consuming endeavor. New electrochemical cells are typically tested under conditions appropriate for known systems and are charged and discharged many times to test reversibility. Such experiments may require weeks or months of cycling before definitive data are obtained. There is then considerable incentive to develop additional testing procedures that will complement the existing techniques and will reduce the time required to make decisions about the usefulness of new battery couples. Additionally, novel testing procedures can be useful in the analysis of performance criteria for existing commercially available battery systems.